Field of the Invention
The present invention relates to a control method of a sensor disposed in an exhaust system, by which moisture formed on sensors disposed in an exhaust line is evaporated and the sensors are then heated to improve the durability of the sensors and prevent malfunctioning.
Description of Related Art
In general, an exhaust line is equipped with sensors (Lambda sensors, nitrogen oxide sensors, PM sensors, or temperature sensors) that are required to be heated by sensor heaters.
These sensors should be heated after evaporating all moisture, such as condensed water, to protect related parts. That is, when power is applied to the sensor heaters before moisture evaporates, an electric shock (short circuit) may damage peripheral parts due to the generation of high current/high-temperature heat.
In reality, if the engine stops working, the exhaust line is cooled to produce condensed water, and this condensed water is formed in the form of moisture on each sensor. When the engine is started and the temperature of exhaust gases rises, the moisture formed on each sensor evaporates.
When power is applied to the sensor heaters that heat the sensors, with moisture present on each sensor, this may deteriorate the durability of the sensors and cause the sensors to operate abnormally, as described above.
As a related conventional technology, Patent NO. 2995-051554 was disclosed which relates to an apparatus and method for preheating an oxygen sensor.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.